Yin & Yang
by Dr. Robert Kienitz, D.Ac., DTCM
The fundamental premise of Chinese philosophy is the concept of the Unity of Opposites.
The short hand way of describing everything that is contained in the physical universe is to say that all things are governed by the rule of the unity of opposites. An even shorter version of describing the same thing is to say that the universe is ruled by Yin and Yang.
The Unity of Opposites first appears in the Book of Changes (also known as the I Ching), in 221 B.C. It forms the basic theory for the Yellow Emperors Classic of Internal Medicine (Nei Jing), civilization’s first comprehensive account of medical science.
The logic system at work in the unity of opposites is dialectical and not linear. In the book Plain Questions it is stated that “Yin and Yang are the laws of heaven and earth, the great framework of everything , the parents of change, the root and beginning of life and death”.
Mater and functions that have impelling, promoting, warming and stimulating effects are Yang. Those elements that have moistening, inhibiting, contracting effects are Yin. Everything in the universe can be categorized as Yin or Yang and some of those classifications follow:
| Yang | Yin | Yang | Yin | Yang | Yin |
| up | down | hot | cold | light | dark |
| dry | wet | out | in | male | female |
| anger | depression | movement | stillness | summer | winter |
| generating | consolidating | function | substance | sun | moon |
The Yin/Yang nature of a phenomenon is not absolute but relative. Under certain conditions Yang may become Yin and vice versa. Yin and Yang may constantly subdivide within each other but the basic nature of Yin must remain Yin and the basic nature of Yang must remain Yang. That is, a thing may be made up of an infinite combination of Yin/Yang components, it may be ninety-nine parts Yin and one part Yang, its basic nature is Yin. Another thing may be made up of fifty-one parts Yang and forty-nine parts Yin, its basic nature is Yang.
The basic contents of Yin/Yang theory reflect their struggle to control one another. In the opposition of Yin/Yang they try to reach equality and maintain balance but there is never true balance for more than a moment. Like two kids on a teeter-totter, the boy is moving up while the girl is moving down, they come into absolute balance for very brief and rare moments. While the boy is going up he is a Yang element engaged in a Yang movement. While the girl is going down she is a Yin element engaged in a Yin movement. When it is the girl’s turn to go up, she is a Yin element engaged in a Yang movement, but still her basic nature is Yin.
Yin/Yang are interdependent and must be for definition to exist. You cannot know light without the contrast of dark, cold with out the contrast of heat, courage without the contrast of fear. All of these examples have multitudes of gradations. As the sun sets the world becomes gradually darker, a little less Yang and a little more Yin, by increments that can be measured in time and light. Dawn is the starting point of Yang and from dawn till noon is the period of Yang within Yang. At noon Yang has reached its fullest point, forcing a natural but gradual change to Yin. From noon to sunset Yin is within Yang. Sunset brings on Yin within yin which reaches it’s fullest at midnight forcing a natural return to Yang. Midnight to dawn is Yang within yin and the cycle continues. This is the inter-transforming relation ship contained with in the unity of opposites.
Only when Yin or Yang is extreme will the inter-transforming relationship take place. The Yin/Yang theory is used in TCM to explain the organic structure and physiological functions of the body as well as the pathogenic changes that are a guide to clinical diagnosis.